Structure for Casehardening a Fixture of a Guide Plate of a Chain Saw

ABSTRACT

A structure for casehardening a fixture of a guide plate of a chain saw is disclosed and comprises: a metal member being larger than the guide plate and having a slot, the dimension between the two edges of the slot being a sum of the dimension of the outer figure of the guide plate and the dimension of a tolerance, the tolerance being defined as an allowable electrode discharging distance; and at least one cooling structure being disposed around one of the edges utmostly and only having one inlet and one outlet, other useless opens being sealed by sealing structures.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to a structure for casehardening a fixture of a guide plate of a chain saw, more particularly to a metal fixture having the features of simpler manufacturing, precise dimensions, longer life, and easier casehardening.

2. Description of the Prior Art

With reference to FIG. 1, which illustrates a schematic 3-D view of a chain saw in prior arts. A chain saw 10 mainly includes a power portion 11, a chain 12 and a guide plate 13; wherein the power portion 11 is wrapped by a case 14 with a handle 15. The guide plate 13 is to guide the chain 12. Due to that the friction of the guiding plate 13 and the chain 12, the hardness and tenacity of the guide plate 13 should comply with requirements in order to prevent the guide plate 13 is damaged by the chain 12.

With reference to FIG. 2, which illustrates a schematic plane view of a machine to casehardening the guide plate of the chain saw in prior arts. The machine includes: the guide plate 13, a frame 20, a plurality of adjusting screws 21, a plurality of block gages 22, a tolerance 23, and a copper tube 30. The frame 20 is wrapped around by the guide plate 131 which has the plurality of adjusting screws 21 and the copper tube 30. The copper tube 30 may be specially treated in advance so as to form a surface thereof. The tolerance 23 should be kept between the copper tube 30 and the guide plate 13, and the value of the tolerance 23 is 0.5 mm, for example. In practicer the plurality of block gages 22 with the thickness of 0.5 mm is disposed between the copper tube 30 and the guide plate 13, and then the plurality of adjusting screws 21 are disposed at the peripheral of the copper tube 30 in order to let the screws 21 urge the copper tube 30. Such that, the distance between the copper tube 30 and the guide plate 13 will be uniform.

The copper tube 30 is then electrified and generates heat by way of high frequency induction. The guide plate 13 around the copper tube 30 will be promoted in hardness and tenacity thereof. On the other hand, ice water flows in the copper tube 30 in order to cool down the copper tube 30.

Even it seems that everything is ready, the disadvantages are still existed and listed below:

-   1. The copper tube should be pre-machined as needed profile figure.     It will waste time and money to only finish a little job, such as     the external figure of the copper tube. -   2. The pre-process of high frequency induction may need to keep a     certain distance between the guide plate and the copper tube, such     as disposing the block gages, each having the thickness of 0.5 mm,     in between the copper tube and the guide plate, and continuously the     adjusting screws on the frame being urged the copper tube, which is     against the block gages in order to keep the certain distance. It     seems that the whole procedures are complicate, plus that to adjust     the adjusting screws may take time, to equalize all the adjusting     screws may be difficult, and to adjust the arc portion of the copper     tube may hardly be done as well.

SUMMARY OF THE INVENTION

The disadvantages in prior arts to be solved are as as follows:

-   1. The copper tube should be pre-machined as needed profile figure.     It will waste time and money to only finish a little job, such as     the external figure of the copper tube. -   2. The pre-process of high frequency induction may need to keep a     certain distance between the guide plate and the copper tube, such     as disposing the block gages, each having the thickness of 0.5 mm,     in between the copper tube and the guide plate, and continuously the     adjusting screws on the frame being urged the copper tube, which is     against the block gages in order to keep the certain distance. It     seems that the whole procedures are complicate, plus that to adjust     the adjusting screws may take time, to equalize all the adjusting     screws may be difficult, and to adjust the arc portion of the copper     tube may hardly be done as well.

The primary objective of the present invention is to provide a structure for casehardening a fixture of a guide plate of a chain saw. Since the contact surface of the guide plate is to guide the chain of the chain saw, therefore the contact surface should be promoted in hardness and tenacity thereof. On the other hand, procedures to make a fixture may involve forming the external figure of the guide plate, controlling the precision, etc., and the cost is relatively higher. The present invention adopts a whole metal member larger than the guide plate of the chain saw, and a slot of the metal member is thus easily and precisely machined. The dimension between the two edges of the slot is a sum of the dimension of the outer figure of the guide plate and the dimension of a tolerance. A cooling structure is disposed around one of the edges utmostly and only has one inlet and one outlet, other useless opens being sealed by sealing structures, wherein the inlet and the outlet of the cooling structure are for ice water or lower temperature gas coming in and going out in order to lower down the temperature of the fixture and prevent melting or breaking the fixture. Therefore, the fixture will be formed precisely and easily.

The comparison to the prior arts and the present invention are listed below:

-   1. The prior arts needs to prepare the copper tube in advance, and     the figure of the copper tube shall be special, such as non-round     tube, and therefore the cost is relatively higher. The present     invention adopts the whole metal member to form the slot and the     cooling structure by machining, and the accuracy is easily     controlled, the manufacture is simple to make the cost down. -   2. The distance (gap) between the guide plate and the copper tube in     prior arts is difficult to be kept in a static state, so that the     plurality of block gages and adjusting screws may be necessary, but     the adjustment takes time and to equalize all the adjusting screws     is hard. The present invention uses the whole metal member, which is     added a tolerance whine in machining, so that to dispose the guide     plate will be very accurate because of the tolerance. Then the     pre-process to high frequency induction can be finished rapidly.

Other and further features, advantages, and benefits of the invention will become apparent in the following description taken in conjunction with the following drawings. It is to be understood that the foregoing general description and following detailed description are exemplary and explanatory but are not to be restrictive of the invention. The accompanying drawings are incorporated in and constitute a part of this application and, together with the description, serve to explain the principles of the invention in general terms. Like numerals refer to like parts throughout the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects, spirits, and advantages of the preferred embodiments of the present invention will be readily understood by the accompanying drawings and detailed descriptions, wherein:

FIG. 1 illustrates a schematic 3-D view of a chain saw in prior arts;

FIG. 2 illustrates a schematic plane view of a machine to casehardening the guide plate of the chain saw in prior arts;

FIG. 3 illustrates a schematic view of a first preferred embodiment of a structure for casehardening a fixture of a guide plate of a chain saw;

FIG. 4 illustrates a schematic exploded view of the first preferred embodiment;

FIG. 5 illustrates a schematic view of a second preferred embodiment of the structure for casehardening the fixture of the guide plate of the chain saw; and

FIG. 6 illustrates a schematic plane view of the second preferred embodiment.

DETAILED DESCRIPTION OF THE INVENTION

With reference to FIG. 3, which illustrates a schematic view of a structure for casehardening a fixture of a guide plate of a chain saw. The structure includes: a metal member 40, which is larger than the guide plate and has a slot 41, which is formed by a machining machine so as to easily keep precise dimensions thereof, the dimension between the two edges 411 of the slot 41 is a sum of the dimension of the outer figure of the guide plate 60 and the dimension of a tolerance 70, the tolerance 70 is defined as an allowable electrode discharging distance, which is 0.5 mm, and the edges 411 are made precisely and easily due to that the slot 41 is formed on the metal member 40; a cooling structure, which is disposed around one of the edges 411 utmostly and only has one inlet and one outlet, other useless opens are sealed by sealing structures, wherein the inlet and the outlet of the cooling structure are for ice water or lower temperature gas coming in and going out in order to lower down the temperature of the fixture 80 and prevent melting or breaking the fixture 80. Therefore, the fixture 80 will be formed precisely and easily.

With references to FIG. 3 and FIG. 4, illustrating a schematic exploded view of the first preferred embodiment, the cooling structure has a groove 42 close to one of the edges 411 of the slot 41 of the metal member 40, the groove 42 is formed on the surface 401 of the metal member 40 and has the inlet 421, the outlet 422 and a useless open 423, which is on the surface 401 of the metal member 40 and sealed and welded by a metal plate 50 same material as the metal member 40.

With reference to FIG. 5, which illustrates a schematic view of a second preferred embodiment of the structure for casehardening the fixture of the guide plate of the chain saw, the cooling structure 43 can be shaped as a long tube with a plurality of holes and connected to other cooling structures 43, each cooling structure 43 is utmostly disposed around one of the edges 411 of the slot 41 so as to let each cooling structure 43 be adjacent to one of the edges 411 of the slot 41, each cooling structure 43 only has the inlet 431 and the outlet 432, other useless opens 433 are all sealed.

The inlet and the outlet are for ice water or lower temperature gas coming in and going out in order to lower down the temperature of the fixture 80 and prevent melting or breaking the fixture 80.

With reference to FIG. 6, which illustrates a schematic plane view of the second preferred embodiment, since the whole metal member 40 is machined to form the guide plate 60 with the tolerance 70, the slot 41 is then done with precise dimensions. While disposing the guide plate 60 in the slot 41, the tolerance between the guide plate 60 and the fixture 80 is uniform so as to make a fast pre-process.

The metal member 40 is for high frequency induction operations.

The advantages of the present invention are listed below:

-   1. A pre-determined tolerance is added while in making the fixture.     Thus the following installing high frequency equipment process is     finished rapidly, and the tolerance is kept uniformly. -   2. The way to manufacturing the fixture is very simple, and the time     to adjusting the guide plate of the chain saw is save     simultaneously.

Although this invention has been disclosed and illustrated with reference to particular embodiments, the principles involved are susceptible for use in numerous other embodiments that will be apparent to persons skilled in the art. This invention is, therefore, to be limited only as indicated by the scope of the appended claims. 

1. A structure for casehardening a fixture of a guide plate of a chain saw comprising: a metal member being larger than the guide plate and having a slot, the dimension between the two edges of the slot being a sum of the dimension of the outer figure of the guide plate and the dimension of a tolerance, the tolerance being defined as an allowable electrode discharging distance; and at least one cooling structure being disposed around one of the edges utmostly and only having one inlet and one outlet, other useless opens being sealed by sealing structures.
 2. The structure for casehardening the fixture of the guide plate of the chain saw according to claim 1, wherein the cooling structure has a groove close to one of the edges of the slot of the metal member, the groove has the inlet, the outlet and a useless open, which is on the surface of the metal member and sealed and welded by a metal plate.
 3. The structure for casehardening the fixture of the guide plate of the chain saw according to claim 1, wherein the cooling structure can be shaped as a long tube with a plurality of holes and connected to other cooling structures, each cooling structure is utmostly disposed around one of the edges of the slot so as to let each cooling structure be adjacent to one of the edges of the slot, each cooling structure only has the inlet and the outlet, other useless opens are all sealed.
 4. The structure for casehardening the fixture of the guide plate of the chain saw according to claim 1, wherein the inlet and the outlet are for ice water or lower temperature gas coming in and going out.
 5. The structure for casehardening the fixture of the guide plate of the chain saw according to claim 1, wherein the metal member is for high frequency induction operations.
 6. The structure for casehardening the fixture of the guide plate of the chain saw according to claim 1, wherein the allowable electrode discharging distance is 0.5 mm. 